Exonucleases are enzymes that work by cleaving nucleotides one at a time from the end (exo) of a polynucleotide chain. For example, eukaryotes and prokaryotes have three types of exonucleases involved in the normal turnover of mRNA.
Various applications in which polynucleotides can be desirably protected in environments where exonucleases are present (e.g. a cell environment) are known in the field of biology and in particular, in the field of biological molecule analysis.
In particular, protection of polynucleotides from exonucleases can be desired in applications aimed at obtaining controlled delivery of analytes of interest to specific environments. Whether for medical applications or for fundamental biology studies, several methods are commonly used for the delivery of various classes of biomaterials and biomolecules which involve delivery of one or more polynucleotides in cell environments or other environments where exonucleases are present.
For example, protection of polynucleotide in specific environments where exonucleases are present, e.g. specific cell types and/or tissues of individuals in vitro and/or in vivo is currently still challenging, especially when directed at providing controlled release of the polynucleotides in a controllable conformation, typically associated to a biological activity.